From “Application of tubular articles in cryoadsorption pumps//Carbon adsorbents and their application in industries.”, Breslavets K. S et al, Moscow, Science publishers, 1983, p. 243, a method for producing a porous carbon article is known. The method comprises a step of forming or extrusion of a paste consisting of silicon carbide powder and commercial synthetic resins as a binder in order to produce a desired article. In this case, transport porosity of the material is formed with pore size above 100 nm. Then a carbonization in an inert medium is carried out in order to strengthen the article and make its structure more uniform. Further the article undergoes a thermochemical treatment by chlorine at 900–1000° C. for transformation of carbide into carbon. In this step, in the volume of the article a nanoporous structure with pore size less than 10 nm is formed.
Use of a polymeric resin as a binder is an obstacle for obtaining high mechanical strength, because of the low mechanical strength of carbonized resin. Resin destruction accompanies formation of carbon which also takes part in the process of forming nanoporosity, but the size of this porosity is practically uncontrollable. As a result, it is impossible to produce materials with predetermined adsorption properties with the known method.
An article produced by means of the known method is a carbon material binded with products of resin carbonization with porosity of 65 to 75 vol % in this case, a part of the pores, 30–32 vol % are transport pores having size greater than 100 nm, while other pores have size less than 10 nm.
Application of articles obtained by the known method is restricted because it gives no possibility to obtain controllable size of pores as well as controllable volumetric content of both transport porosity and nanoporosity.
A number of so called activated carbons with a high content of nanoporosity is known, but the pore size distribution for these materials is very wide and uncontrolled, c.f. “Carbon”, John Wiley & Son, N.Y. 1988,USA.
It is thus a need for a method in which the porosities of a porous carbon material which comprise two types of pores can be controlled. The two types are pores of a size less than 10 nm providing adsorption ability and pores of a size greater than 100 nm providing transportation of a component to the pores taking active part in the adsorption process. Articles produced by such a method can be used in different fields of technology connected with adsorption and absorption processes, such as selective absorption of a component from a liquid or gas, electrochemical electrodes, in medicine technologies, etc.
The object of the present invention is to make it possible to produce carbon porous articles with predetermined transport porosity and predetermined nanopore sizes, volume and distribution throughout the volume of the article.